Analysis of the pattern of suprahyoid muscle activity during pharyngeal swallowing of foods by healthy young subjects

Abstract

We previously developed the T_P technique to discriminate between the activity patterns of skeletal muscles. In this study we aim to identify the T_P value(s) that can be used to sensitively evaluate the activity patterns of the suprahyoid (SH) muscles during swallowing. We also analyse the effect of food textural properties on the activity patterns of the SH muscle during oral and pharyngeal swallowing. Three test foods consisting of 3%, 6% and 9% of a thickening agent, Mousse-up (MU) were prepared. Their textural properties differed significantly. Swallowing of 9% MU involved a significantly longer average duration than 3% MU. The average T₅₀ value for 6% MU was significantly larger than that for 3% MU. However, the average T₂₀ and T₈₀ values of the test foods did not differ. Thus, the T₅₀ value is particularly suitable for evaluating SH muscle swallowing patterns. Moreover, test foods that vary in their textural properties elicit different durations and patterns of SH muscle activity.

Keywords:

• Muscle activity pattern
• Suprahyoid muscle
• Swallowing
• Texture
• Normal subject

Acknowledgments

This study was supported in part by a Grant-in-Aid for Scientific Research of Younger Researchers (to I.A.) from the Niigata University of Health and Welfare and by a Grant-in-Aid for Scientific Research (No. 19500667 to Y.M.) from the Ministry of Education, Science and Culture of Japan.